Preparation of vinylglyoxal derivatives, novel vinylglyoxal derivatives and their use

摘要

Vinylglyoxal derivatives of the general formula I <IMAGE> (I) where R is straight-chain or branched alkyl or alkenyl, cycloalkyl or unsubstituted or substituted phenyl, are prepared by a process in which bicyclo[2.2.1]hept-5-enecarbaldehyde of the formula V <IMAGE> (V) is either (a) subjected to autocondensation with formation of a compound of the formula VII <IMAGE> (VII) or (b) reacted with a compound of the general formula II R-CH=O (II) where R has the above meanings, with formation of a mixture of the compounds of the general formulae VIII (a) and (b) <IMAGE> (VIIIa) <IMAGE> (VIIIb) where R is as defined above, in the presence of a catalyst, and the compound of the formula VII or the compounds of the formulae VIII (a) and (b) is or are oxidized to the corresponding dicarbonyl compounds, after which gas-phase pyrolysis is carried out at from 500 DEG to 700 DEG C. and under reduced pressure, in particular less than 10-1 mbar, and, if desired, the resulting compound of the general formula I is further purified. These compounds can be used, for example, as monomer components in polymeric systems.